Barack Obama - Theresa May first official meeting planned
It will be the first official meeting between the two leaders since May took office in July after David Cameron quit following the British vote to leave the European Union.
Obama had spoken out strongly against a Brexit, warning voters in the referendum their nation would go "to the back of the queue" for a US trade deal if they opted to leave.
In Hangzhou, the two leaders "will discuss a range of bilateral and global issues, and, as close friends and steadfast allies, the United States and United Kingdom continue to enjoy an enduring special relationship," the official said.
The US leader will also meet with Turkish counterpart Recep Tayyip Erdogan, with whom relations have become more complex following the country's intervention in Syria.